Core Barrel Stabilizer

ABSTRACT

A core barrel stabilizer that offers a simple solution in creating an initial drilling kerf in conjunction with a hollow core barrel for drilling large diameter holes into the earth for a plethora of construction needs. The core barrel stabilizer includes a centering rod for keeping the core barrel stabilizer and hollow core barrel centered during drilling the initial perimeter kerf, an eyelet hook for easily maneuvering the core barrel stabilizer between drill holes and transportation, and an inner barrel used to rest the inner wall of the hollow core barrel against during drilling to ensure the drilling kerf can be started.

CROSS REFERENCE TO RELATED APPLICATIONS

U.S. Pat. No. 4,671,367

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable to this application.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates generally to an improved technique for drilling relatively large-diameter holes using a core barrel and a newly designed core barrel stabilizer for construction piling for buildings, bridges, and the like.

2. Description of the Related Art

In the drilling industry, it is desired to drill relatively large diameter holes in the bedrock of the earth ranging from 36 inches to 48 inches and up. These holes can be utilized for a multitude of construction desires to accomplish foundation work, access-holes, etc. Typically, a complete hole is drilled using a large cluster drill or gang drill driven by a large crane or excavator combined with a rotary head or Kelly-bar drive. Another means is through the same type of setup, but with the use of a core barrel. Instead of drilling the entire surface area, the core barrel only drills the perimeter with the core either completely removed or left in after drilling a varied depth.

A more efficient and economical means to drilling theses large diameter holes is through the use of a core barrel paired with a core barrel stabilizer instead of large cluster drills or gang drills. These core barrels are typically double walled and house stationary, vertically oriented, air hammers between the walls that extend just slightly past the bottom of the walls. The hammers typically are circular in design and have multiple protruding tungsten carbide buttons that chip away the rock when the hammers are engaged via air. As the core barrel either oscillates or rotates 360-degrees, the hammers pulverizes the rock surface creating a cutout perimeter the size of the core barrel diameter. Air is supplied through the double wall design to feed the rock hammer bits and to blow out the rock debris up and out of the exterior of the core barrel. By drilling the perimeter of the hole only, significant time, energy, and money can be saved instead of drilling the entire surface area of the hole. Depending on the desired application, the resultant inner rock core can either be removed or left in place. The advantages with this core barrel style design is the reduced operating cost due to only cutting the perimeter of the hole instead of the entire surface area.

One major short coming to this style of drilling that can be further improved upon is the equipment needed to initially create the core barrels kerf in the drilling surface. As stated above, current methods use large cranes and or excavators to hold and secure the core barrel in place as the core barrel tries to create an initial kerf, but for smaller residential or spatially restrictive construction areas, this type of equipment is not practical due to sheer size and equipment cost. The large cranes and or excavators must hold the core barrel in its exact location, as the core barrel creates its initial kerf in the ground. Even with the larger equipment used for drilling, creating the initial kerf in uneven or unconsolidated ground can be extremely difficult as the rotation of the core barrel and the vibration of the core barrel hammers will cause a “walking effect” on the drilling surface. This “walking effect” results in the core barrel to no longer be concentric with the initial starting point making it extremely difficult to create the initial kerf in the precise location for the core barrel.

Previous methods to overcome this issue are disclosed in U.S. Pat. No. 4,671,367. This method uses a guide pin connected to the Kelly bar to avoid lateral movement of the core barrel to complete the initial kerf. This method requires a large crane and or excavator paired with a Kelly bar drive that can be extremely costly and difficult to setup in smaller construction areas.

BRIEF SUMMARY OF THE INVENTION

What is needed is a core barrel stabilizing apparatus which is suitable for any core barrel drilling size crane and or excavator but does not suffer from the disadvantages of being directly attached to the Kelly bar drive on the large crane and or large excavator. Said device can be removed and set aside completely from the core barrel once the initial kerf is created, and can be utilized on cranes and or excavators that do not already have a guide pin directly coupled to the Kelly bar drive.

Accordingly, an object of the present invention is to provide a core barrel stabilizer that is completely and easily removable from the ground once the initial kerf is created in the drilling surface.

Another object of the present invention is to provide a simple drop-in solution to be utilized with a core barrel to avoid the core barrel from moving laterally on the drilling surface when the initial kerf is trying to be created.

A further object of the present invention is to provide a core barrel stabilizer that does not need to be manufactured into the Kelly bar drive.

A final objective would be for this invention to be used with any crane and or excavator that does not have a means of stabilizing the core barrel during the creation of the initial kerf.

In satisfaction of these and other objects, the invention provides a pilot tube connected to a large circular hollow exterior tube with a lifting eye to keep the core barrel stabilized during the start of drilling. The pilot tube is preferably made from a hollow tube and extends down past the exterior of the inner barrel. The inner barrel is made from steel with two end caps welded on each end. The eyelet hook is welded to the topside of the pilot tube, and is to be used to move the core barrel stabilizer in and out of position.

The core barrel stabilizer has an outer diameter that is just slightly smaller than the insider core barrel diameter. Typically, the core barrel inside diameter could be anywhere from 18 inches all the way up to 60 inches, depending on the size of the core barrel being used for the drilling process. In practice, the core barrel stabilizer inner barrel will be large enough to have a minimum gap clearance between the core barrel and the core barrel stabilizer to ensure a proper kerf can be made in the beginning stages of drilling.

In operation, a pilot hole, the size of the pilot tube on the core barrel stabilizer, is drilled to a depth that is sufficient enough to secure the core barrel stabilizer in the ground via the pilot tube. Once the pilot hole is drilled, the core barrel stabilizer is lifted, via the eyelet hook, by a crane and or excavator into position. The core barrel stabilizer is in position once the pilot tube is resting on the bottom of the pre-drilled pilot hole or once the core barrel stabilizer is resting on the ground.

Once the core barrel stabilizer is inserted into the pre-drilled pilot hole, then the core barrel is carefully set over the inner barrel of the core barrel stabilizer until one or more of the core barrel hammers come in contact with the ground. After the core barrel is in place, over the core barrel stabilizer, the drill operator engages the core barrel to begin drilling. Air is supplied to the rock hammers to begin drilling, and the core barrel begins to either rotate 360-degrees or oscillate between a specific angle, depending on the core barrel design. The operator continues to drill, with the core barrel stabilizer guiding the hammers along the same perimeter circle to avoid lateral movement of the core barrel, until the initial kerf is created, and all the hammers on the core barrel have a kerf to follow for the remainder of the drill. Once the initial kerf is created, the core barrel is lifted off the core barrel stabilizer. The core barrel stabilizer is then lifted out of the pre-drilled pilot hole and set aside for the next drill. The core barrel is than set back onto the drilling surface, where the initial perimeter kerf has been created through the help of the core barrel stabilizer, and drilling commences again until the final depth is obtained.

A core barrel stabilizer according to the present invention does not require the crane or excavator to have a pre-design pilot tube system built into the machine for the core barrel, unlike conventional methods of drilling with a core barrel. In addition, it has numerous advantages over large-diameter core barrel drilling processes that must have a pilot tube designed into the crane and or excavator Kelly bar drive. Since the core barrel stabilizer is a separate unit, significant costs can be reduced on the initial purchase of the crane and or excavator used for drilling with the core barrel. Another advantage to the core barrel stabilizer is utilizing a core barrel and core barrel stabilizer with a much smaller crane and or excavator. This allows for significant fuel savings, noise reductions, and drilling can be accomplished in more spatially restrictive construction sites.

BRIEF DESCRIPTION OF THE DRAWINGS

Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:

FIG. 1 is a side view of a core barrel stabilizer according to the present invention.

FIG. 2 is a cross-sectional view of a core barrel stabilizer taken along section A-A of FIG. 1, particularly showing the core barrel stabilizer eyelet hook, inner barrel, and centering rod.

FIG. 3 is a top view of a typical core barrel comprising of multiple hammers positioned on the outer perimeter with a drive adaptor in the center.

FIG. 4 is a bottom view of a typical core barrel comprising of multiple hammers positioned on the outer perimeter.

FIG. 5 is a side view of a core barrel, without a core barrel stabilizer, positioned on the ground at any given angle between 0 and 90-degrees.

FIG. 6 is a top view of a core barrel without a core barrel stabilizer positioned on the ground.

FIG. 7 is an exploded view of a core barrel, with a core barrel stabilizer, and the ground with a pre-drilled pilot hole.

FIG. 8 is a side view of a core barrel, with a core barrel stabilizer, positioned on the ground at the start of the drilling process.

FIG. 9 is a side view of a core barrel, with a core barrel stabilizer, positioned on the ground at the end of the drilling process, in which, the initial drilling kerf has been created.

FIG. 10 is a rear view of a core barrel, with a core barrel stabilizer, positioned on the ground at the end of the drilling process, in which, the initial drilling kerf has been created.

FIG. 11 is a cross-sectional view of a core barrel and core barrel stabilizer, positioned on the ground at the end of the drilling process, in which, the initial drilling kerf has been created.

FIG. 12 is an exploded view of a core barrel, with a core barrel stabilizer, and the ground after the initial drilling kerf has been created.

DETAILED DESCRIPTION OF THE INVENTION A. Overview

Turning now descriptively to the drawings, in which similar reference characters denote similar elements through the several figures. FIGS. 1 through 10 illustrate a core barrel stabilizer 1 paired with a core barrel 2, which the core barrel stabilizer 1 comprises a centering rod 4 for keeping the core barrel stabilizer 1 centered, an eyelet hook 5 that is utilized for easily maneuvering the core barrel stabilizer 1 into and out of position, and an inner barrel 6 to center the core barrel 2 during the initial creation of the drilling kerf.

B. Core Barrel Stabilizer

The core barrel stabilizer 1 is comprised of a centering rod 4, an eyelet hook 5, and an inner barrel 6 as shown in FIGS. 1 and 2. Generally, the centering rod 4, is welded concentric to the inner barrel 6, with the eyelet hook 5 welded to the inside of the centering rod 4 in such a way to accommodate enough room for a chain, cable, strap, etc. to connect to eyelet hook 5 as shown in FIG. 2.

The diameter of the inner barrel 6 varies in size based off the core barrel 2 being used in the drilling process as a multitude of core barrel 2 diameters are available for drilling. The diameter of inner barrel 6 should be as large as possible, as to clear the core barrel 2 inside diameter and rock hammers 7 shown in FIG. 11. The length of inner barrel 6 of the core barrel stabilizer 1 should not extend past the core barrel 2 rock hammers 7 shown in FIG. 11.

The diameter of the centering rod 4 should be slightly less than that of the pre-drilled pilot hole 9 as shown in FIG. 11. Typically, this can range from 4-12 inches in diameter. The length of the centering rod must be such that the core barrel stabilizer 1 is stable enough to keep the core barrel 2 in position before and after the initial kerf 10 is created as shown in FIGS. 8 and 11.

C. Core Barrel

The core barrel 2 is typically comprised of a circular metal structure, in which, the inside of the structure, between the rock hammers 7 around the exterior perimeter is hollow, and a drive adapter 8 is securely fastened to the top of the core barrel 2 that is used to turn the core barrel 2 during operation as shown in FIGS. 3, 4, and 11.

D. In Use

In use, the core barrel stabilizer 1 is used as an assisting device to create an initial drilling kerf 10 with core barrel 2. To do so, an initial pilot hole 9 must be drilled into the ground 3 as shown in FIG. 7. Once an initial pilot hole 9 is drilled into the ground 3, the core barrel stabilizer 1 can be hoisted into place via the eyelet hook 5 shown in FIGS. 2 and 7. The centering rod 4 of the core barrel stabilizer 1 shown in FIG. 2 is used to keep the core barrel stabilizer 1 in position as the core barrel 2 is placed over the core barrel stabilizer 1 in FIGS. 7 and 8. Once the core barrel 2 is placed over the core barrel stabilizer 1 as shown in FIG. 8, the core barrel 2 begins to rotate around the core barrel stabilizer 1 via the drive adapter 8 on the core barrel 2 and the rock hammers 7 are pressurized with air to begin the drilling process shown in FIG. 6. The core barrel 2 will slowly drill downward into the ground 3 until a sufficient drilling kerf 10 has been created as shown in FIGS. 9 and 11. The kerf 10 should be deep enough in the ground 3 such that the core barrel 2 rock hammers 7 can use the drilling kerf 10 as a guide for the remainder of the drill as shown in FIG. 11. Once the kerf 10 has been created, the core barrel 2 and the core barrel stabilizer 1 are removed from the ground 3 as shown in FIG. 12. The core barrel stabilizer 1 is completely removed via eyelet hook 5 for the remainder of the drilling process. The core barrel 2 is repositioned with the rock hammers 7 centered inside the kerf 10 as shown in FIG. 9, and the drilling process can continue to the desired depth.

What has been described and illustrated herein is a preferred embodiment of the invention along with some of its variations for the inventions possible circuitry on a core barrel 2. The terms, descriptions and figures used herein are set forth by way of illustration only and are not meant as limitations. Those skilled in the art will recognize that many variations are possible within the spirit and scope of the invention, which is intended to be defined by the following claims (and their equivalents) in which all terms are meant in their broadest reasonable sense unless otherwise indicated. Any headings utilized within the description are for convenience only and have no legal or limiting effect. 

1-2. (canceled) 3: A removable core barrel stabilizer (1) for assisting a core barrel (2) in the initial creation of a drilling kerf (10) in an even or uneven ground (3) during the start of drilling with a core barrel (2), whereas a rigid centering rod (4) is connected in the center of a cylindrical inner barrel (6), in which, the centering rod (4) gets positioned concentric into a ground pilot hole (9) by means of an eyelet hook (5), and the inner barrel (6) fits snug on the inside of the core barrel (2), after the core barrel (2) is placed over the inner barrel (6), in order to drill into a ground (3) surface concentrically. 